The present invention relates to minimally invasive coronary artery bypass grafting (CABG) procedures and in particular to perfusion device for use in performing minimally-invasive microsurgeries such as internal mammary artery (IMA) or vein graft to coronary artery surgery procedures while maintaining blood flow distally in the LAD during the construction of the anastomosis, to prevent ischemia while further maintaining a dry anastomosis site to facilitate the surgery procedure.
Surgeons constantly are striving to develop advanced surgical techniques resulting in turn in the need for developing advanced surgical devices and instruments required for the performance of such techniques. Recent advances in the surgical field increasingly are related to operative techniques which involve less invasive surgical procedures and reduce overall patient trauma. To illustrate, in the field of CABG procedures it has been common practice for surgeons to perform a sternotomy to expose the body cavity in the thorax region, wherein retractors are employed to provide the surgeons the access required to perform the necessary bypass surgery.
However, more recent surgical techniques employ less invasive CABG procedures known as endoscopic surgery involving the use of an endoscope instrument which permits the visual inspection and magnification of any cavity in the body, such as the thorax cavity. The procedure involves the insertion of tubes called a trocar cannulas through the soft tissue protecting the body cavity. The surgeon then performs diagnostic and therapeutic procedures at the surgical site with the aid of specialized micro-instrumentation designed to fit through the various trocar cannulas that provide the required openings into the body cavity.
In such endoscopic techniques, an arterial blood source such as the IMA is dissected from its location, transected and prepared for attachment at an anastomosis site on a selected coronary artery, commonly the LAD. To this end, a portion of the LAD is exposed and an incision is made in the arterial wall. The distal end of the IMA is then sutured over the incision in the LAD to conclude the bypass graft surgery.
However, in order to perform the above surgical procedures, heart activity must be arrested. Thus, to maintain the patient, it is necessary first to divert the patient's blood circulation through an extracorporeal cardiopulmonary bypass system. This is accomplished by isolating the heart at selected arterial locations using selected catheter instruments and occluders to draw the blood into the bypass system for oxygenation thereof via an associated pump oxygenator. The oxygenated blood is returned to the patient to maintain the patient's systemic circulation during the surgery. The procedure further includes the ligating of vessels by pinching off the vessel with sutures and/or the use of occluder devices in the artery, the functions of which are to prevent the flow of blood through the artery to maintain a dry surgical site during the suturing of the anastomosis.
Accordingly, typical cardiovascular surgical procedures such as that of previous mention include the procedures of placing the patient on a cardiopulmonary bypass system and then inducing cardioplegic arrest of the heart in situ in the patient's body. It follows that the entire anastomosis construction is performed with the heart in the arrested state, and with special precautions taken to prevent any blood flow in the vessel on which the anastomosis surgery is being performed. To this end, an occluder device which is sometimes inserted in the blood vessel to isolate the anastomosis site is specifically configured to be impenetrable to thereby prevent the flow of blood through the occluder device at the anastomosis site.
The surgical procedures of previous mention experience the disadvantages of increased trauma to the arteries caused by ligatures, to the heart due to the cessation of blood flow to distal portions thereof, and to the patient in general due to the cardiopulmonary bypass and cardioplegic arrest procedures and instruments. Accordingly, it would be highly desirable when performing a bypass surgery to circumvent the problems of previous mention, that is, to obviate the need for a cardiopulmonary bypass procedure and to allow the anastomosis construction to be performed without the occlusion of blood flow through the associated blood vessel, to prevent ischemia while still maintaining a dry anastomosis site to facilitate the suturing procedure.